akumbhani66/encrypt-decrypt.html

## encrypt-decrypt.html
<!DOCTYPE html>
<html>

<head>
  <title>File Encryption/Decryption</title>
</head>

<body>
  <h1>File Encryption/Decryption</h1>

  <h2>Encryption</h2>
  <input type="file" id="fileInput" onchange="previewFile(event)" />
  <img id="previewImg" style="max-width: 300px; display: none;" />
  <input type="text" id="secretKey" placeholder="Enter secret key" />
  <button onclick="encryptFile()">Encrypt File</button>
  <a id="downloadEncryptedLink" style="display: none;">Download Encrypted File</a>

  <h2>Decryption</h2>
  <input type="file" id="encryptedFileInput" />
  <input type="text" id="decryptionKey" placeholder="Enter secret key" />
  <button onclick="decryptFile()">Decrypt File</button>
  <a id="downloadDecryptedLink" style="display: none;">Download Decrypted File</a>

  <script>
    function previewFile(event) {
      const file = event.target.files[0];
      const previewImg = document.getElementById('previewImg');

      if (file) {
        const reader = new FileReader();
        reader.onload = () => {
          previewImg.src = reader.result;
          previewImg.style.display = 'block';
        };
        reader.readAsDataURL(file);
      } else {
        previewImg.src = '';
        previewImg.style.display = 'none';
      }
    }

    function encryptFile() {
      const file = document.getElementById('fileInput').files[0];
      const secretKey = document.getElementById('secretKey').value;

      if (!file || !secretKey) {
        alert('Please select a file and enter a secret key.');
        return;
      }

      const reader = new FileReader();
      reader.onload = async () => {
        const fileBytes = new Uint8Array(reader.result);
        const iv = window.crypto.getRandomValues(new Uint8Array(16));
        const encryptedBytes = await encryptData(fileBytes, secretKey, iv);

        // Combine IV and encrypted bytes
        const combinedBytes = new Uint8Array(iv.length + encryptedBytes.length);
        combinedBytes.set(iv);
        combinedBytes.set(encryptedBytes, iv.length);

        const encryptedBlob = new Blob([combinedBytes], { type: file.type });
        const encryptedUrl = URL.createObjectURL(encryptedBlob);

        const downloadLink = document.getElementById('downloadEncryptedLink');
        downloadLink.href = encryptedUrl;
        downloadLink.download = `encrypted_${file.name}`;
        downloadLink.style.display = 'inline';
      };
      reader.readAsArrayBuffer(file);
    }

    async function encryptData(data, secretKey, iv) {
      const cryptoKey = await window.crypto.subtle.importKey(
        'raw',
        new TextEncoder().encode(secretKey),
        { name: 'AES-CBC' },
        false,
        ['encrypt']
      );

      const encryptedBytes = await window.crypto.subtle.encrypt(
        { name: 'AES-CBC', iv },
        cryptoKey,
        data
      );

      return new Uint8Array(encryptedBytes);
    }

    function decryptFile() {
      const encryptedFile = document.getElementById('encryptedFileInput').files[0];
      const secretKey = document.getElementById('decryptionKey').value;

      if (!encryptedFile || !secretKey) {
        alert('Please select an encrypted file and enter the secret key.');
        return;
      }

      const reader = new FileReader();
      reader.onload = async () => {
        const combinedBytes = new Uint8Array(reader.result);

        // Extract IV and encrypted bytes
        const iv = combinedBytes.slice(0, 16);
        const encryptedBytes = combinedBytes.slice(16);

        const decryptedBytes = await decryptData(encryptedBytes, secretKey, iv);

        const decryptedBlob = new Blob([decryptedBytes], { type: encryptedFile.type });
        const decryptedUrl = URL.createObjectURL(decryptedBlob);

        const downloadLink = document.getElementById('downloadDecryptedLink');
        downloadLink.href = decryptedUrl;
        downloadLink.download = `decrypted_${encryptedFile.name}`;
        downloadLink.style.display = 'inline';

        const img = document.createElement('img');
        img.src = decryptedUrl;
        document.body.appendChild(img);
      };
      reader.readAsArrayBuffer(encryptedFile);
    }

    async function decryptData(encryptedData, secretKey, iv) {
      const cryptoKey = await window.crypto.subtle.importKey(
        'raw',
        new TextEncoder().encode(secretKey),
        { name: 'AES-CBC' },
        false,
        ['decrypt']
      );

      const decryptedBytes = await window.crypto.subtle.decrypt(
        { name: 'AES-CBC', iv },
        cryptoKey,
        encryptedData
      );

      return new Uint8Array(decryptedBytes);
    }
  </script>
</body>

</html>
	<!DOCTYPE html>
	<html>

	<head>
	<title>File Encryption/Decryption</title>
	</head>

	<body>
	<h1>File Encryption/Decryption</h1>

	<h2>Encryption</h2>
	<input type="file" id="fileInput" onchange="previewFile(event)" />
	<img id="previewImg" style="max-width: 300px; display: none;" />
	<input type="text" id="secretKey" placeholder="Enter secret key" />
	<button onclick="encryptFile()">Encrypt File</button>
	<a id="downloadEncryptedLink" style="display: none;">Download Encrypted File</a>

	<h2>Decryption</h2>
	<input type="file" id="encryptedFileInput" />
	<input type="text" id="decryptionKey" placeholder="Enter secret key" />
	<button onclick="decryptFile()">Decrypt File</button>
	<a id="downloadDecryptedLink" style="display: none;">Download Decrypted File</a>

	<script>
	function previewFile(event) {
	const file = event.target.files[0];
	const previewImg = document.getElementById('previewImg');

	if (file) {
	const reader = new FileReader();
	reader.onload = () => {
	previewImg.src = reader.result;
	previewImg.style.display = 'block';
	};
	reader.readAsDataURL(file);
	} else {
	previewImg.src = '';
	previewImg.style.display = 'none';
	}
	}

	function encryptFile() {
	const file = document.getElementById('fileInput').files[0];
	const secretKey = document.getElementById('secretKey').value;

	if (!file \|\| !secretKey) {
	alert('Please select a file and enter a secret key.');
	return;
	}

	const reader = new FileReader();
	reader.onload = async () => {
	const fileBytes = new Uint8Array(reader.result);
	const iv = window.crypto.getRandomValues(new Uint8Array(16));
	const encryptedBytes = await encryptData(fileBytes, secretKey, iv);

	// Combine IV and encrypted bytes
	const combinedBytes = new Uint8Array(iv.length + encryptedBytes.length);
	combinedBytes.set(iv);
	combinedBytes.set(encryptedBytes, iv.length);

	const encryptedBlob = new Blob([combinedBytes], { type: file.type });
	const encryptedUrl = URL.createObjectURL(encryptedBlob);

	const downloadLink = document.getElementById('downloadEncryptedLink');
	downloadLink.href = encryptedUrl;
	downloadLink.download = `encrypted_${file.name}`;
	downloadLink.style.display = 'inline';
	};
	reader.readAsArrayBuffer(file);
	}

	async function encryptData(data, secretKey, iv) {
	const cryptoKey = await window.crypto.subtle.importKey(
	'raw',
	new TextEncoder().encode(secretKey),
	{ name: 'AES-CBC' },
	false,
	['encrypt']
	);

	const encryptedBytes = await window.crypto.subtle.encrypt(
	{ name: 'AES-CBC', iv },
	cryptoKey,
	data
	);

	return new Uint8Array(encryptedBytes);
	}

	function decryptFile() {
	const encryptedFile = document.getElementById('encryptedFileInput').files[0];
	const secretKey = document.getElementById('decryptionKey').value;

	if (!encryptedFile \|\| !secretKey) {
	alert('Please select an encrypted file and enter the secret key.');
	return;
	}

	const reader = new FileReader();
	reader.onload = async () => {
	const combinedBytes = new Uint8Array(reader.result);

	// Extract IV and encrypted bytes
	const iv = combinedBytes.slice(0, 16);
	const encryptedBytes = combinedBytes.slice(16);

	const decryptedBytes = await decryptData(encryptedBytes, secretKey, iv);

	const decryptedBlob = new Blob([decryptedBytes], { type: encryptedFile.type });
	const decryptedUrl = URL.createObjectURL(decryptedBlob);

	const downloadLink = document.getElementById('downloadDecryptedLink');
	downloadLink.href = decryptedUrl;
	downloadLink.download = `decrypted_${encryptedFile.name}`;
	downloadLink.style.display = 'inline';

	const img = document.createElement('img');
	img.src = decryptedUrl;
	document.body.appendChild(img);
	};
	reader.readAsArrayBuffer(encryptedFile);
	}

	async function decryptData(encryptedData, secretKey, iv) {
	const cryptoKey = await window.crypto.subtle.importKey(
	'raw',
	new TextEncoder().encode(secretKey),
	{ name: 'AES-CBC' },
	false,
	['decrypt']
	);

	const decryptedBytes = await window.crypto.subtle.decrypt(
	{ name: 'AES-CBC', iv },
	cryptoKey,
	encryptedData
	);

	return new Uint8Array(decryptedBytes);
	}
	</script>
	</body>

	</html>